Error Codes

HTTP responses and SOCKS5 reply codes from the Proxies.fo network

Error codes differ by product. Residential has a richer set of plan-limit and targeting errors; Datacenter has a tighter set focused on authentication and upstream failures plus SOCKS5 reply codes.

Residential

Authentication & request errors

400 Bad Request · standard

Your HTTP request is malformed. Check your proxy client is sending a valid HTTP CONNECT or request line.

407 Proxy Authentication Required · standard

Username or password is wrong, or your targeting modifiers contain an unrecognised value.

Body: Incorrect username or password

417 Expectation Failed · standard

Your client sent an Expect: header the proxy can’t satisfy. Remove it or switch libraries.

Plan limit errors

452 Bandwidth Exceeded · custom

You’ve used all the bandwidth on your plan. Top up or upgrade from the dashboard.

Body: exceeded bandwidth limit

453 Thread Limit Exceeded · custom

You’re making more concurrent connections than your plan allows. Lower concurrency or upgrade.

Body: exceeded threads limit

Targeting errors

454 Invalid Country Code · custom

The country-<code> modifier isn’t a recognised country. Use lowercase ISO 3166-1 alpha-2 codes (e.g. us, de, jp).

Body: invalid country code

454 Invalid State Code · custom

The state-<code> value isn’t recognised for the country you picked. Use the standard regional subdivision code.

Body: invalid state code

454 Invalid City Code · custom

The city-<n> value isn’t recognised, or no IPs are available for that city. City names should be lowercase and concatenated (westlakevillage, not Westlake Village or westlake-village).

Body: invalid city code

454 Invalid ASN · custom

The asn-<number> value isn’t in the supported ASN set, or no IPs are available for the combined geo + ASN targeting. Verify the ASN with whois or bgp.he.net. If the ASN is valid but no IPs are returning, widen your geo targeting.

Body: invalid asn

455 Invalid TTL · custom

The ttl-<minutes> value is outside the allowed range. TTL must be a positive integer within the supported lifetime range.

Body: invalid ttl

Upstream errors

502 Bad Gateway · standard

The target site couldn’t be reached. Could be DNS failure, target-side refusal, or a transient network issue. Retry with backoff.

500 Internal Server Error · standard

An unexpected error occurred. If you see this repeatedly, contact support with a timestamp.

503 Service Unavailable · standard

A transient internal error. Retry with backoff — if it persists, contact support.

Residential summary

Code	Meaning	Action
400	Bad request	Fix client request format
407	Auth failed	Check username / password
417	Expectation failed	Remove Expect: header
452	Bandwidth exhausted	Top up plan
453	Thread limit hit	Lower concurrency or upgrade
454	Invalid country / state / city / ASN	Fix targeting modifier
455	Invalid TTL	Use a valid ttl-<minutes> value
500	Internal error	Contact support
502	Upstream unreachable	Retry with backoff
503	Service unavailable	Retry; contact support if persistent

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Datacenter (HTTP)

400 Bad Request · standard

Malformed authentication — typically a bad Base64-encoded Proxy-Authorization header. Your proxy client is sending credentials in the wrong format. Regenerate or re-encode.

407 Proxy Authentication Required · standard

Missing, invalid, expired, or capped credentials. Common causes:

• Username or password is wrong
• Session credentials have expired
• Plan bandwidth or thread limit reached
• Account suspended or expired

Check the dashboard to confirm your plan status.

500 Internal Server Error · standard

Server-side error encountered after authentication succeeded. Inspect the X-Server-Error response header for a more specific reason.

curl -v -x "http://user:[e-mail]:10808" https://api.ipify.org
# Look for: < X-Server-Error: <reason>

If the header isn’t present or the reason isn’t clear, contact support with the request timestamp.

Datacenter HTTP summary

Code	Meaning	Action
400	Bad auth encoding	Check Base64 of Proxy-Authorization
407	Auth failed / expired / capped	Verify creds and plan status
500	Post-auth server error	Inspect X-Server-Error header

Datacenter (SOCKS5)

SOCKS5 replies use single-byte reply codes in the response to the initial CONNECT or UDP ASSOCIATE request. These are standard SOCKS5 codes — most libraries surface them as descriptive error messages automatically.

0 — Succeeded

The connection was established. No error.

1 — Network Unreachable

The network to the target is unreachable from our upstream. Usually transient — retry with backoff.

2 — Host Unreachable

The specific host can’t be reached. DNS may have resolved, but no route to the destination. Check the target is up.

3 — Connection Refused

The target actively refused the connection. The target port may be closed, or the target is rejecting your traffic.

4 — Command Not Supported

You sent a SOCKS5 command we don’t support. Stick to CONNECT for TCP and UDP ASSOCIATE for UDP.

SOCKS5 summary

Code	Meaning	Action
0	Succeeded	—
1	Network unreachable	Retry with backoff
2	Host unreachable	Check target availability
3	Connection refused	Target rejected — check port / target state
4	Command not supported	Use CONNECT or UDP ASSOCIATE only

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Handling errors in code

Python (residential)

import requests

proxy = "http://adminpcowe-country-zz:[e-mail]:13337"
proxies = {"http": proxy, "https": proxy}

try:
    r = requests.get("https://api.ipify.org", proxies=proxies, timeout=30)
    if r.status_code == 454:
        print("Targeting error:", r.text.strip())
    elif r.status_code == 452:
        print("Out of bandwidth — top up your plan")
    elif r.status_code == 453:
        print("Too many concurrent connections")
    elif r.status_code >= 500:
        print(f"Upstream issue ({r.status_code}) — retry with backoff")
    else:
        print(r.text)
except requests.exceptions.ProxyError as e:
    print("Auth failed — check credentials:", e)

Anything unexpected? Reach out on Telegram with a request timestamp.